In various wireless communications systems a number of different base station attachment points may be available to an access terminal at the same time. Some of the different available base station attachment points may correspond to different carriers and/or sectors. Communications capabilities between the access terminal and the different available attachment points can be expected to be different for different attachment points at different times, e.g., as a function of access terminal location, transmission signal strength, channel gain, interference, noise, etc. In addition attachment point loading conditions can be expected to vary throughout the system and over time.
Different end users in a wireless communications system will typically have different needs, e.g., depending on the amount of traffic, type of traffic and/or device capabilities. In addition different end users may be contracted to be provisioned differently, from a service provider perspective. Different data rate requirements and/or different latency requirements may correspond to different users at a given time.
It is desirable to be able to efficiently utilize the available air link resources in a system including multiple alternative attachment points to maximize throughput and enhance user experience. Load balancing in such a system is an important consideration. There is a need for a handoff mechanism that facilitates load balancing in a wireless communications system while taking into effect different device needs and/or different service levels. A centralized system control node approach to load balancing may not be practical or efficient to implement, e.g., due to system architecture, control signaling overhead and/or control signaling delays.
A mobile access terminal may be in the best situation to evaluate its current channel conditions with respect to potential alternative attachment points. Based on the above discussion, there is a need for novel access terminal based handoff decision methods and apparatus which facilitate load balancing in a wireless communications systems. For an access terminal to make intelligent handoff decisions which contribute to load balancing it would be advantageous if additional base station information was available. Accordingly, there is a need for novel base station methods and apparatus which provide information facilitating access terminal based handoff decisions and system load balancing.